Is Your Thyroid To Blame For Your Sleep Issues?
Many people with sleep issues suffer from low thyroid function, also called hypothyroidism. In the low thyroid state, the cells of the body cannot relax, and the body overproduces stress hormones including cortisol and adrenalin. Especially too high adrenalin makes it difficult to fall and stay asleep. People with low thyroid function often suffer from low blood sugar issues, which also contribute to sleep problems.
Why Low Thyroid People Can't Relax
The problem for hypothyroid people is that they cannot relax because relaxation takes energy. In the low energy state of hypothyroidism, cells are constantly overexcited. Hypothyroid people often feel very tired but they have trouble sleeping and their quality of sleep is also low. In contrast, the high-energy state of good thyroid function makes cells able to relax and regenerate, which makes them ready to work when needed. You can learn more about the consequences of low and high thyroid function in my Thyroid Recovery & Renewal course.
Thyroid Function and Stress Hormones
In the low thyroid state, the body cannot generate enough cellular energy and therefore has to use stress hormones such as cortisol and adrenalin to keep the body going. These stress hormones are stimulating in the short term but they are very harmful if present at high levels for a long time. High levels of stress hormones cause insomnia and fatigue. In addition, high stress hormones over time cause chronic inflammation, hormonal imbalances, and many degenerative conditions.
Healing from insomnia and sleep problems therefore often involves improving thyroid function and lowering stress hormones. I address the hormonal side of this in my Hormone Rebalance Intensive™.
Low Blood Sugar and Sleep
People with low thyroid function often have problems with blood sugar regulation. Low blood sugar during the night causes a spike in stress hormones, which then disrupts sleep. Therefore keeping blood sugar steady throughout the day — and using a small snack of protein and good carbohydrates before bed — can significantly improve sleep quality. The dietary principles for keeping blood sugar stable are covered in my book How to Boost Metabolism with Food and my Metabolic Nutrition Mastery course.
Light and Sleep
Light exposure during the day and darkness at night are important for healthy sleep. In a pro-metabolic approach, getting adequate daylight — or using light therapy when sunlight is limited — supports the hormonal balance that underpins good sleep. Darkness promotes the production of stress hormones and melatonin, whereas daytime light supports the production of protective hormones. I cover light therapy and its effects on hormonal balance in my Pro-Metabolic Lifestyle course.
Frequently Asked Questions
Why does hypothyroidism cause insomnia?
In the low thyroid state, the body does not generate enough cellular energy, so it compensates by overproducing stress hormones — particularly cortisol and adrenalin. These stress hormones are stimulating and make it difficult to fall asleep or stay asleep. Additionally, hypothyroid people often experience low blood sugar during the night, which triggers another stress hormone spike that disrupts sleep. The paradox is that these people feel exhausted but cannot sleep.
Why does relaxation take energy?
This is one of the key insights from Dr. Ray Peat's research. Relaxation — including the cellular relaxation that enables sleep — is an active, energy-requiring process. In a low energy state, cells cannot complete the biochemical steps needed to relax after excitation. This is why hypothyroid people feel wired and tired simultaneously — their cells are overexcited because they lack the energy to switch off. Restoring thyroid function restores the ability of cells to properly relax and regenerate.
Can improving thyroid function improve sleep?
Yes — in my experience both personally and with clients, improving thyroid function is one of the most reliable ways to improve sleep quality. When cellular energy production increases, the need for stress hormones decreases, and cells gain the ability to properly relax and regenerate during sleep. Combining thyroid support with stable blood sugar management and reduced stress hormone levels makes a significant difference. My Thyroid Recovery & Renewal course covers this in full.
What can I do before bed to improve sleep with hypothyroidism?
Keeping blood sugar stable is important — a small snack of protein and good carbohydrates before bed (such as milk with a little honey or fruit) can prevent the nocturnal blood sugar drop that triggers stress hormones and disrupts sleep. Avoiding stimulating activities and bright blue light in the evening also helps. Longer term, the most effective approach is addressing the underlying thyroid function and hormonal imbalances that create the sleep problem in the first place.
